Magneto-electric ignition apparatus



March'IZ, 1935. J. BOHLI GNETO-ELECTRIC IGNITION APPARATUS 5 Sheets-Sheet; 1

Filed July 3, 1933 Jnran for MM-MA March 12, 1935. J. BOHLI 1,993,325

IAGNETO-ELECTRIC IGNITION APPARATUS Filed July 3, 1933 3 Sheets-Sheet 2 fly. a.

Jn ran/9r Patented Mar. 12, 1935 MAGNETS-ELECTRIC IGNITION APPARATUS Jakob Bohll, Solothurn, Switrerland Application July 8, 1933, Seth! No. 678,900

In Germany July 4, 1932 3 Claims. (CL 171-252) The present invention relates to the members cylindric ends oi the conducting bars 1-, s, t abut of a magneto electric ignition apparatus which against the lower cylindric end 10'. These conconduct the magnetic flux through the ignition ducting bars are laminated and fixed in the cascoil. The star shaped members used up to now ins @1- Besides ey are guided y $19 ribs 1! 5 for transmitting the flux through the ignition and 1/ oi the covers as md x. The course of 5 coil have conical holes fitting the conical ends the flux is as follows: Permanent magnet 0, conoi the coil core. This design is not satisiacconducting bar i oil core is conducting has i. tory as it is difllcult to get an intimate iit heand back to permanent magnet c. tween the star shaped conducting members and With the exception of the air gap between the the conical ends of the-coil core. In some places conducting bars and the permanent magnet 10 an air gap remains between the conical hole 01 there are only two more connections at the ends this conducting member and the ends of the oi the coil core, which however represent a very coil core affecting the path of the flux from that small reluctance. As the ends w and w of the member to the core and thereby reducing the eiiicore are cylindric and as the ends oi the conl5 ciency of the apparatus. ducting bars are turned out cylindrically also,

The object of this invention consists in that a very good fit oi the conducting bars on the the arms oi said flux conducting members which coil core is obtained; thereby the losses oi the arms are at right angles to the axis oi the ignimagnetic flux are reduced to a minimum. tion coil are turned out cylindrically and firmly In the example at Fig. 3 the conducting bars pressed against the cylindric ends oi the coil 1;, o, p are U-shaped with arms oi diiierent 20 core, and that in another constructional iorm length. The conducting bars r, s, tare .Z-shaped, these conducting members are made longer than their arms having diflerent lengths also. The usual and have such a shape that they form at shorter arms of the U-shaped conducting bars the same time the coil core itself. These conand the longer arms of the Z-shaped conducting g3 ducting members are laminated. The core porbars form together the coil core in such a way tion of each sheet of one conducting piece is that the shorter arm of each U-shaped conarranged between the core portions 01 two sheets ducting sheet is arranged between the longer of the adjacent conducting pieces and vice versa. arms of two Z-shaped conducting sheets and On the drawings constructional forms oi the vice versa. The longer arms of the U-shaped :0 object of the invention are shown. conducting bars and the shorter arms of the Fig. 1 is a longitudinal section through the Z-shaped conducting bars complete the magnetic ignition apparatus with a stationary cell on line connection to adjacent arms oi the permanent E-E 01 Fig. 2. a magnet. In the planes in which Z-shaped con- Fig. 2 is a plan view or the conducting memducting sheets form part of the coil core, an bers and of the ignition cell on line 3-3 of L-shaped conducting sheet is used between the 35 Fig. 1. U-shaped sheets. In a similar way L-shaped Fig. 3 is a longitudinal section of another consheets are provided between the Z-shaped sheets structional form of the ignition apparatus with where the shorter arms of U-shaped sheets form a stationary coil on line F--F oi Fig. ii. the core sheets. With the exception of the air Fig. iisalongitudinal section oi aiurther con gap between the conducting bars and the pole 40 structional form of the ignition apparatus. wheel, there are no more air gaps thereby the Fig. 5 is a plan view of the conducting pieces conditions with respect to the reluctance to the and ot the pole wheel on line D-D according to course oi the flux; are still better than in the case the example of Fig. 4. oi the example illustrated in Figs. land 2.

Fig. 6 is a cross section through the coil core. This new method of designing the conducting 45 In the example 01 Figs. 1 and 2 it represents bars and the coil core is not only applicable to the bearing bracket for the drive shaft h of magneto electric ignition apparatus with statione -fi d permanent magnet w c i Sta! ary coil and rotating pole wheel, but also to shaped with any number of arms. (1 is the ignisuch apparatus with stationary pole wheel and 5p tion coil and g the laminated core oi the latflux distributor or to apparatus with rotating coil ter which has at both ends a cylindric part a: systems and stationary permanent magnets. and 10'. In the case of a permanent magnet In the example of Figs. 4 and 5 the conducting with six pole arms the cylindric ends of three bars n, c, p, are L-shaped and their shorter arms L-shaped conducting bars 11., o, p abut against abut against the upper cylindric end of the coil I the upper cylindric end w 01 the coil core. The core 9. At the lower cylindric end 01' this coil 66 coreasetofsheetswiththreearmsnatare arranged at right angles to the core axis. The ends of the arms of the permanent magnet are bent of! parallel to the axis of rotation (compare the parts'c' to c"'') and are fitted with lamination sheets A. The course of the flux is similar to that of the first example, i. e.: arm 0' of the permanent magnet c, conducting bar n, coil core 0, arm 1', arm c" of the permanent magnet and back to the arm 0 of the permanent magnet.

As mentioned above, the coil core itself is laminated. As shown in Fig. 6, the single sheets of the lamination are wedge-shaped and mounted together in such a way that they form a round core. In this way the round section of the core is fully utilized and a round hole in the centre is obtained. The drive shaft of the breaker cam and high tension distributor extends through the entire length of this hole. Further the conducting of the flux-from the conducting bars of the coil core is favourable as the sections of the conducting bars and of the sheets or the coil core are parallel to each other and do notcross one another as is the case in known designs. Up to now the lamination of the coil core has been made in such a way that a strip of sheet iron was rolled up. A core made in this way often caused short circuits at its ends. In other cases the lamination has been made in such a way that strips of sheet iron of various widths were mounted together in the form of a triangle, but in such designs the round section of the core is not fully utilized.

What I claim is:

1. In a magneto electric ignition apparatus in combination a drive shaft, a rotating permanent magnet, a stationary ignition coil, L-shaped fiux conducting bars, one arm of which is at a right angle to the axis of rotation and the end of the said arm being turned out cylindrically, a laminated coil core, both ends of which are cylindric, the sheets of said coil core having wedge-shaped section and being adapted to form a round core with a central round hole, said L-shaped conducting bars being mounted in such a way that they are adapted to abut against the ends of said coil core, end plates for the ignition coil, ribs on said end plates adapted to keep the sheets of the conducting bars firmly together, a bearing bracket for the drive shaft, a casing for the ignition apparatus in which said conducting bars are fixed.

2. In a magneto electric ignition apparatus in combination a drive shaft, a rotating permanent magnet wheel, the ends of the arms of which are bent oil parallel to the axis-of rotation, a stationary ignition coil, L-shaped flux conducting bars one arm of which is at a right angle to the axis of rotation and the end of said arm being turned out cylindrlcally, a laminated coil core, both ends of which are cylindric, said L-shaped conducting bars being mounted in such a way that they are adapted to abut against the end of said coil core, a star-shaped laminated fiux conducting member arranged at right angles to the axis of rotation and fixed to the lower end of said coil core, end plates for the ignition coil, ribs on said end plates adapted to keep the sheets of the conducting bars firmly together, a casing for the ignition apparatus in which said conducting bars are fixed.

3. In a magneto electric ignition apparatus in combination a drive shaft, a rotating permanent magnet, a stationary ignition coil, laminated U-shaped fiux conducting bars, laminated Z- shaped flux conducting bars, L-shaped sheets, the shorter arm of said U-shaped conducting bars and the longer arm of said Z-shaped conducting bars, being adapted to form the coil core in such a way that each sheet of one type of conducting bar is arranged between two sheets of the adiacent other type Qnducting bars, and L-shaped sheets being placed each between two sheets of the U-shaped conducting bars in the planes in which portions of the sheets of the Z-shaped conducting bars form parts of the coil core, and between two sheets of the Z-shaped bars in the planes in which portions of the sheets of the U-shaped bars form parts of the coil core, end plates for the ignition coil, ribs on said end plates adaptedto keep the sheet of the conducting bars firmly together, a bearing bracket for the drive shaft, a casing for the ignition apparatus in which said conducting bars are fixed.

I JAKOB BOHLI. 

